Alternative biome states challenge the modelling of species' niche shifts under climate change
Juli G. Pausas, William J. Bond
Abstract
Abstract It is common to characterise the species niche using climate and global species distribution maps. This is then used to predict changes in distribution under a warming climate. This approach assumes that climate is a major driver of species distribution and that each species responds individually (sensu Gleason) to climate. However, in many world landscapes, for a given climate, strikingly different vegetation types co‐occur: forests and non‐forests. These two alternative biome states are maintained by different feedback processes and have radically different species with contrasting shade and disturbance tolerance traits. We propose that to improve predictions of species distribution changes under a novel climate, we need to consider the presence or absence of forest shade, as species are likely to respond individually only within their forest or non‐forest biome, and not across biomes. Synthesis . By considering shade as a biotic filter in niche modelling, we are not only improving our predictive capacity, but we are also reconciling the two views of communities: both the individualistic (within biome) and the organismal (across biomes) views of the community concept become relevant and complementary.